Long staple drafting mechanism



B. 'J. Z ALKIND LONG STAPLE D RAF' I'ING MECHANISM Aug. 26,1941.

'Filed Aug. 8. 1944 s sheets-sum 1 Aug. 26, 1947. B. J. ZALKIND V 2,426,425

I LONG STAPLE DRAFTING IECHANISI Filedjug. e, 1944 s Sheets-Shea; 2

2 9 7. B,-J. ZIALKIND I I 2,425,425.

LONG STAPLE nmnue imcmxsn Filed Aug. 8, 1944 3 sheen-s ut s Patented Aug. 26, 1947 LONG STAPLE DRAFTIN G ltiECHANISM Benjamin. J. Zalkind, Saco, Maine, assignor to Saco-Lowell Shops, Boston, Mass., a corporation of Maine Application August 8, 1944, Serial No. 548,535 I 6 Claims. (01. 19-131) This invention relates to drafting mechanisms for spinning and roving frames, hereinafter referred to collectively as spinning frames.

The rapidly increasing use of long staple roving such, for example, as rayon and mixtures of cotton with wool or rayon. or both, has introduced difficult problems in the spinningof these materials in cotton spinning frames. naturally are equipped with drawing mechanisms designed for handling a considerably shorter staple. While the mere increase of roll spacing to accommodate longerfibers can readily be accomplished in new designs, that does not afford the control of the fibers necessary to the production of good yarn.

It is generally recognized that good drafting requires adjustment of the roll spacing to a value slight in excess of the length of the staple being vrun. This is essential not only for the orderly drawing of the fibers from the roving into a strand of even composition so that the yarn spun from it will be of the required degree of uniformity, but is equally important in properly drafting out the bunch produced in splicing up the roving. Naturally as the range of staple to be handled in a'given mechanism is increased, the necessity for frequent adjustment of the roll spacing correspondingly increases. Moreover, if an apron-type of drafting mechanism is used similar to that, for example, of the well known Saco-Lowell-Roth system, then an increase in roll spacing tends to produce a sag in the upper run of the apron where it passes through the drafting zone and thus to create conditions definitely unfavorable to the drafting operation.

The present invention deals especially with the foregoing considerations, and it aims to devise a spinning frame which will accommodate the entire range of staples from the longer, but common cotton lengths, such as one inch, up to those lengths used in mixtures of the character above described in which the staple will run to inv the neighborhood of two and a half. to about three inches, or somewhat more. It is also an object of the invention to devise a thoroughly practical drafting mechanism of the apron-type .in which the adjustments necessary for the foregoing purpose will be reduced to a minimum and no adjustment of the apron tension or the parts controlling that tension will be required.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying'drawings, and the novel features will be particularly pointed out in the appended claims.

The latter 2 In the drawings: Fig. 1 is a sectional elevation of a draftingmechanism embodying this invention; Figs. 2, 3. and 5 are vertical, sectional views showing different ways in which the rolls may be arranged in the mechanism shown in Fig. 1;

Fig. 4 is a perspective view of two adjacent cap bars forming parts of this mechanism; and

Fig. 6 is a plan view, on a larger scale, of the saddle shown in Fig. 5.

Referring first to Figs. 1 and 2, the construction there shown comprises a set of lower rollsineluding a front roll 2, an intermediate roll 3, and a back roll 4. These rolls are fluted or knurled, as shown, and are driven positively from a gearing mechanism located at one end of the spinning frame, as is customary in machines of this type. A series of roll stands, one of which is shown in Fig. l at 5, support the rolls, these stands being, in general, of a common form, exceptthat each includes a bearing block 6 having sockets to receive the necks of the intermediate and rear lower rolls 3 and 4, respectively. It supports them in a fixed relationship to each other, but the block itself is mounted on a ribbed guiding arm I for I adjustment toward and from the front roll 2. A

cap screw 8 passing through a slot in the arm 1 and threaded into a tapped hole in the block 6, locks the block in its adjusted position.

Riding on the rolls 3 and 4 is a belt or apron I0 which also runs over a stationary guide bar l2, located between the front and middle rolls 2 and 3, respectively. A weighting roll l3, Fig. 1, rests in the loop of this apron and maintains a constant tension on it. The lower rolls 3 and 4 cooperate with the weighted top roll l8 to drive the apron I 0, the greater part of the driving effort being performed by either of these bottom rolls into contact with which the top rollpresses the apron.

In this arrangement the apron has an exceptionally long, straight, upper reach, substantially in line with the bite of the front rolls for supporting and guiding the roving; it is driven at a constant but considerably slower speed than the front roll 2 and it is here utilized as a lower holding member cooperating with any one of afseries of upper roll arrangements to control the roving or sliver as it is drawn forward by the front rolls. Naturally the difference in speed at which the front rollsand the apron areoperated will depend upon the drafting requirements of the particular staple being run.

' Cap bars,'such as those shown in Figs. "1 and 4, are pivoted on the rod l4 and serve to hold the top rolls in the desired spaced relationship to each other and in the proper cooperative relationship to the bottom rolls. The particular cap bar shown at IS in Fig. 1 is like that indicated by the same number inFig, 4, except that it is reversed, these two bein the bars at the opposite ends of the frame section, while the bar I6, Fig. 4, is an intermediate bar. Referring to the latter figure, it will be seen that the bar includes front, rear and middle cap bar blocks or sections A, B and C, block B being adjustable on a rod D which also is adjustably fixed in the section C by the long screw 32. The adjustable section carries a set screw by means of which it may be locked to said rod in the desired position and the front block A is pinned to the rod. Corresnonding sections on the intermediate bar are illustrated by the same, but primed, letters. It will also be observed that the front sections A and A have notches a and a to receive the gudgeons at the o posite ends of the front top rolls I! and additional notches or shoulders b, c, d and e are provided in the other sections to accommodate the gudgeons of additional top rolls. One large rear roll only, indicated at I8, is used in each set, but this roll is placed in either of the notches d, d, or e and e, where it is directly over the lower intermediate-roll 3 or the lower rear roll 4, depending upon the setting required for the length of the staple being run.

Between this roll I 8 and'the front top roll ll, one, two or three slip rolls may be placed, as shown in Figs. 2, 3 and 5, to cooperate with the apron in controlling the fibers in the extremely long space between the rolls I1 and I8. The best results are obtained by graduating the weightof these slip rolls, the front slip roll 20 being made heaviest and the rear roll the lightest.

This construction permits the drafting of staple varying from the cotton lengths of, say, one inch or an inch and a quarter, 'to the mixed fiber lengths of in the neighborhood of three inches or three and a half inches, with a minimum of adjustment of the rolls. Assuming; for example, that cotton alone is being run, an arrangement such as that illustrated in Fig. 2 would be used, the weighted rear roll l3 being positioned directly over the intermediate bottom roll 3. In this arrangement the lower front and middle rolls may be assumed to be spaced apart on centers of approximately an inch and a half to an inch and three-quarters, which spacing, combined with the presence of the slip roll 20, afiords reasonably satisfactory conditions for drafting the better grades of cotton.

If, now, the staple is changed to a two inch mixture, then the weighted rear roll I8 is simply placed in the notches e and e where it bears on the apron directly over the lower rear roll 4, as shown in Fig, 3, and the slip roll 2| which previously had been resting in the notches e is moved forward into the notches d-d' where it takes the position formerly occupied by the weighted roll. This change in position of the roll I8 increases the roll spacing by the fixed distance between the intermediate and rear lower rolls 3 and '4, respectively, which distancenormally is in the neighborhood of one inch. Such an arrangement is suitable for drafting staple of the length just mentioned, and without any adjustment of the lower rolls,

For still longer staples, say two and a half or three inches long, the bearing block 6 may be adjusted away from the front rolls into some such position as that illustrated in Fig. 5, the

cap bars moving with the block 6 because of the fact that the bearing for their pivot bar i4 is secured to, or is made integral with, the block 6, as shown in Fig. l. Preferably, a third slip roll 22 is introduced between the other two slip rolls, as also indicated in Fig. 5.

Other staple lengths may be accommodated in the same manner, but the fact that the intermediate and rear bottom rolls are spaced apart by a fixed distance, and the cap bars are constructed to support the rear weighted top roll interchangeably over either of said lower rolls in all positions of adjustment of the bearing block 6, makes it possible to change the roll spacing from one fixed value to another, differing from it by a distance equal to the spacing of the latter rolls, merely by shifting the top weighted roll l8 from one of its operative positions to another. This operation can be performed very quickly, requires no skill, and often saves the making of a considerably more laborious adjustment.

It should also be observed that these changes in roll spacing do not affect the tension on the apron or require any adjustment of the tapetensioning roll. It automatically takes its proper position. In addition, the fact that the upper reach of the apron, where it runs through the drafting zone, is supported not only at its ends but also at an intermediate point by the roll 3, is an important factor in maintaining this reach of the apron substantially flat and prevents any degree of sag likely to interfere with the drafting operation.

The weighting mechanism provided for the top rolls may be eitheradjustable or non-adjustable, as desired. An adjustable type is illustrated in Figs. 1, 2 and 3, including a stirrup i3 connected, for example, to the usual weighted lever commonly used, and having a head 24 at its upper end with a tapered end screw 25 threaded through said head and bearing in a socket f, Fig. 2, in the saddle 26. This is a satisfactory arrangement for a narrow spacing of the top weighted rolls. When that spacing is increased the screw 25 may be shifted into another socket behind the socket f, as shown in Fig, 3, where a better distribution of the weight then will be obtained.

This saddle has a long straight surface g to bear on the neck of the roll 18 in any of its operative positions.

For most purposes the non-adjustable saddle 21, shown in Figs. 5 and 6, will be found as satisfactory as the adjustable type and eliminates an adjusting operation. It has a body much like that illustrated in Fig. 2, but is provided with a slotted neck through which the head 24' of the stirrup 13 projects, and. to which it is fastened by a pivot pin 28. I

The usual brackets for supporting a clearer 30 for the top front roll are mounted on, or made integral with, the front section A of the cap bars, and an apron clearer 3|, Fig. 1, may be supported on posts 32, Figs. 1 and 4, secured in the section 0 of the cap bar.

When the small rod 2| is located behind the rear top roll l8, as in Fig. 2, it performs no function, so far as the drawing operation is concerned, but it does serve a very useful purpose when a, new bobbin of roving is to be threaded up. At that time the end of the roving is threaded through the trumpet, which normally is positioned immediatel behind the bite of the rearmost upper and lower rolls. This end is grabbed by the Z'Jli 2i and the apron the normal method of threading up. but if the roll 2% were not in the position shown in Fig. '2 when the roli spacing is shortened up, as shown in that figure, thenit would be necessary to thread the roving through the trumpet and pull it manually into the nip of the roll l8.

It has been definitely determined in actual mill operation that this mechanism handles thelong staple'rov'ing of the character above described in an exceptionally satisfactory manner and produces good yarn at a material reduction in production costs as compared to the prior art drafting systems now available commercially for use with long staple. It has been proved, further, that it makes a better piecing when a new bobiii, and is fed for-. ward by them into its running position. This is bin of this type of roving is spliced in, than does any other drafting mechanism of which I have been-able to learn.

Having thus described my invention, what I desire to claim as new is:

1. In a drafting mechanism for spinning frames, the combination with driven front, middle and back lower rolls, a bar between said front and middle rolls, roll stands supporting said rolls in definite spaced relationship to each other, an apron having an upper reach supported by said bar. and by said middle andback rolls, said upper reach being substantially straight, said apron being driven by both of the latter rolls, a front top roll running in contact with said front bottom roll; a rear weighted top roll running in contact with said apron, cap bars supporting said top rolls in their operative positions, said cap bars being provided with shoulders in spaced fixed relation to each other for supporting said rear top roll directly over either the middle or rear bottom roll, as desired, to accommodate difierent lengths of staple, said upper rear roll when positioned above said lower rear roll serving to drive the apron and feed the staple and means i for weighting said top rolls, said means includ-' ing means for weighting the rear top roll in both of its operative positions.

2. A drafting mechanism according to preceding claim 1, in combination with a slip roll located immediately behind said front top roll and restsecond slip roll resting on said apron between bar having notches to support said rear top roll ing claim 1, in which each of said roll stands includes a bearing block supporting said middle and rear bottom rolls in a fixed spaced relationship to each other, said bearing blocks being adjustable toward and from said front roll, and means for looking said blocks in difierent positions of ad- .iust'ment,

4. In a drafting mechanism according to preceding claim 1, in which said weighting means for the top rolls includes a saddle having a socket to engage the neck of the" front top roll and a long tail portion to bear on the neck of said rear weighted top roll in all of its adjusted positions. I

5. In drafting mechanism according to preceding claim 1, a construction in which each of said roll stands includes a block having bearing sockets supporting said middle and rear lower rolls in fixed spaced relationship to each other, each block being mounted in its respective stand for adjustment toward and from the front roll, and means for securing each of said blocks in its adjusted position, the bearing sockets for said middle and rear lower rolls being spaced apart by a distance of between an inch and one and one-quarter inches.

6. A drafting mechanism according to preceding claim 1, in which each of said roll stands ineludes bearing blocks supporting the middle and back lower rolls at a fixed distance from each other of between an inch and one and one-quarter inches, each roll stand including also means for supporting said blocks for adjustment to vary the spacing of said middle lower roll from said front lower roll from a distance of about an inch and a half between centers to at least two and one-half inches between centers, the spacing of the middle and rear lower rolls from each other remaining unchanged.

ing on said apron directly above said bar, and a and the second slip roll interchangeably above said middle and rear bottom rolls, as desired. 1

3. A drafting mechanism according to preced- BENJAMIN J. ZALKIND.

REFEa'ENcEs cr'ran The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,644,747 Both Oct. 11, 1927 1,285,643 Dixon Nov. 26, 1,918 2,189,368 Pilling Feb. 6, 1940 1,827,385 Cornibert Oct. 13, 1931 FOREIGN PATENTS Number Country Date 9,692 Great Britain 1915 506,713

GreatBritaln June 2, 1939 

